It is well known in the vehicle industry that certain rotary accessory devices are often used in connection with vehicle motors. Two such accessory devices are alternators and starter motors. Alternators are used in connection with an engine and are typically belt driven by the engine. Alternators have internal components, which when rotated supply electrical power to a vehicle and/or an engine. Alternators are typically removable but rigidly mounted via a bracket to the engine block or the chassis of the vehicle. In many cases, where a standard type of alternator mounting arrangement is used, the alternator has “ears” with holes that are mounted onto a post or bolt attached to the vehicle. This permits pivoting of the alternator so that the alternator can be pivoted around the post against the belt tension in order to install and remove belts, and provide a suitable tension when the belt is installed.
Starter motors are electrical motors, which are typically removable but rigidly mounted to an engine or transmission casing. The starter motor has an electrically driven pinion gear extending from the starter motor that engages a component (typically gears on the flywheel of the engine) in order to be able to rotate the crankshaft of the engine to start it. There is a wide range of attachment mechanisms for attaching the described starter motor.
Conventional alternator and starter tester may test alternators and/or starter motors using a direct current (DC) power source. For example, the DC power source may be used to power the starter motor and bias the alternator during a testing process. The DC power source may determine the capability of an alternator and starter tester. Oftentimes, the alternator and starter tester has limited capabilities because of the available power supply. The maximum rating of the alternator and starter tester is determined by the available power supply and an efficiency of the tested equipment. However, the tested equipment may have different efficiencies or be defective and may lead to tripping of the available power supply protection. Thus, it would be desirable to have an alternator or starter tester with active load control circuitry to monitor an input power level.